Add 21/8 and 18/42
1st number: 2 5/8, 2nd number: 18/42
21/8 + 18/42 is 171/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 42 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
18/42 = 18 × 4/42 × 4 = 72/168 - Add the two like fractions:
441/168 + 72/168 = 441 + 72/168 = 513/168 - 513/168 simplified gives 171/56
- So, 21/8 + 18/42 = 171/56
In mixed form: 33/56
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